There is no API linkage to Kitsun atm.
However there are several ways to add you WK studied words into Kitsun that are pretty simple:
- WaniKani Known Kanji & Vocab Filter : you tag your completed WK levels and ‘add to known’ Kitsun database for both vocab and kanji
- There is the WaniKani Reversed deck. This will naturally add the known base into Kitsun as you do your lessons alongside WK (vocab only)
Personally, I’d prefer not to have the API linkage. I’ve gone back on studied WK items in order to have full dictionary synonym buildouts and the ability to have Eng->Jp layout within the same review session (and not use some separate SRS). So I prefer to selectively add what I know to the Kitsun known base.